The U.S. telecommunications industry is evolving in anticipation of rigorous competition for market share in local and long distance services. It is competition, and the expectations of the modem day consumer, that drive telecommunications companies to quickly bring to market those products and services which provide competitive pricing, quality service and convenience. One example of such a service is the now familiar "calling card" which allows a subscriber to place toll calls while away from the home or office without having to bill the call to a third party or to continually insert coins into a public telephone. A typical calling card enables a user to dial a directory number of a called party and a calling card number to place a call. Upon validation of the dialed calling card number by an operator services system (OSS), a connection between the caller and the called party is established. The calling card subscriber subsequently pays for the telephone call, and all other calls placed during a predetermined period, upon receiving an itemized calling card bill. Alternatively, the calling card may carry a pre-established (i.e., prepaid) balance as described in the U.S. patent application of Wanda K. Cross et al. entitled "Method For Establishing Customized Billing Arrangements For A Calling Card In A Telecommunications Network", Ser. No. 08/526,794, filed Sep. 11, 1995, which is assigned to AT&T Corp. and incorporated by reference herein. Prepaid calling cards carry a non-billed balance enabling the user to place telephone calls using the number printed on the face of the card until the balance is depleted. As the balance nears depletion, the typical user contacts the issuing company for another prepaid card. Consequently, it is not unusual for a single user to retain multiple, prepaid calling cards with varying balances.
An inconvenience associated with retaining multiple, prepaid calling cards results from current network implementations which require callers to limit usage to one calling card account per call. In other words, if the remaining balance on a prepaid calling card is insufficient to allow a conversation of a desired length, the caller is forced to disconnect the call at calling card balance depletion and reoriginate the call with a different calling card. This process necessarily creates extra dialing for the caller as special access numbers, menu options, the new calling card number and called party's telephone number must be reentered before the call can be established again. Further, in addition to extra dialing, an interruption of the telephone conversation between the caller and called party is required. Since ease-of-use is the hallmark of any calling card service, inconveniences associated with prepaid calling card use may result in a loss of market share for calling card issuing companies. Therefore, there is a need in the art for accommodating multiple calling card billing of a single call in a telecommunications network.